An analysis of ancient crops has suggested that Madagascar inhabitants may have Asian origins. The study provided new clues to the mysteries of Madagascar's colonization.

Past genetic studies already confirmed the Madagascar inhabitants' ancestral link to Polynesians and Malaysians. However, archeologists have failed to find evidence for the group's early presence in Madagascar until now.

A team of international researchers analyzed the preserved remains of ancient plants obtained using a process called flotation. This process utilizes water and sieves to separate the residues from the sediment.

The team used the remains found at 18 ancient settlement sites in coastal eastern Africa, Madagascar and the Comoros. This enabled the team to identify 2,443 individual crop remnants under a microscope.

"What was amazing to us was the stark contrast that emerged between the crops on the Eastern African coast versus those on Madagascar, and the more we looked, the starker the contrast became," said lead author Alison Crowther from The University of Queensland.

African crops such as pearl millet, baobab and sorghum dominated the ones found on the eastern African coast as well as the nearest islands to Madagascar. These crops had been existing on the areas for several centuries when farmers traveled through the continent.

The Madagascar excavation sites yielded remnants of Asian crops such as mung bean, Asian cotton and Asian rice. The African crops found here bordered from very few to none.

In the course of their investigation, they created a robust theory that the Asian crops reached Madagascar from the islands of Southeast Asia.

According to senior author Nicole Boivin from the Max Planck Institute for the Science of Human History, findings showed that Southeast Asians brought the Asian crops to Madagascar, planted them and survived on them.

The findings also suggested that the early Southeast Asians colonized the nearby Comoros islands. The ancient crop analysis found on these islands also yielded dominance of Asian crops.

Boivin added the research did not only reveal — for the first time — the Austronesians' first archeological remnant on Madagascar, but its signature also seemed to go beyond the island.

The study findings provided archeologists with new data they can use to create the history of Madagascar's colonization process using material insights. The research is published in the Proceedings of the National Academy of Sciences journal.